Manufacture of molds for casting metal.



iii

T FFTQQ ERNST L. BOI-IL AND ROBERT Y. BARROWS, OF RUTHERFORD, NEWJERSEY.

MANUFACTURE OF MOLDS FOR CASTING METAL.

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N0 Drawing.

T 0 all whom it may concern:

Be it known that we, ERNs'r L. Born and ROBERT Y. BAnRows, citizens ofthe United States, and residing at Rutherford, in the county of Bergenand State of New Jersey, have invented certain new and usefulImprovements in the Manufacture of Molds for Casting Metal, of which thefollowing is a specification, such as will enable those skilled in theart to which it appertains to make and use the same.

This invention relates to molds for casting metal and the object thereofis to provide an improved mold or molds for this purpose by means ofwhich the delicate outlines and designs of a finely wrought pat tern canbe perfectly reproduced in a mold made from or on said pattern; afurther object being to provide a mold for the purpose specified whichwill stand or resist the heat of a furnace and also the heat of themolten materials poured into it without being frac tur-ed or broken.

The invention described and claimed herein is an improvement on thatdescribed and claimed in Letters Patent of the United States granted onthe application of Ernst L. Bohl, one of the applicants herein, on June15, 1909, Number 92%,728.

The patent above referred to covers a process or method of making moldsand other articles which consists in forming a mold or other articlefrom a composition of matter containing plaster of paris, painting orcovering the mold or other article with an oleaginous substance andheating the said mold or other article in an oven, the oleaginoussubstance being melted lard or. any other substance having similarqualities, the object of covering or painting the mold with anoleaginous substance and then heating and drying said mold in an oven,being to prevent-the mold from absorbing moisture from the air orotherwise, the composition employed being preferably plaster of parisand ashes.

It is a wellknown fact that molds of the class specified made of plasterof paris and ashes reduced to a plastic condition by mingling watertherewith and then formed into molds, contain minute pores which are sofine that they cannot, or can scarcely be seen, and molds made in thismanner absorb moisture from the air very readily and this renders themimpractical, or useless for making metal castings, especially castingsof the Specification of Letters Patent.

Application filed September 20, 1909.

Patented June 7, 1910.

Serial No. 518,496.

finer qualities, and castings of brass; but by saturating the mold in anoven with a vapor of oil or oleaginous substance, this propensity of themold for absorbing moisture from the air is greatly lessened if notentirely done away with. In the patent referred to this result isaccomplished as hereinbefore stated, by painting or covering the moldwith the oleaginous substance and then heating the mold or drying it inan oven; and we lILHQ discovered by practical experience that the same,or better results can be secured by-placing the oleaginous substance inany kind or class of a receptacle, in the oven with the mold, or byinjecting a vapor of oil or any other oleaginous substance into the ovenwhile the mold is being heated or dried. In the first case theoleaginous substance is converted into a vapor in the oven, whichvaporsaturates the mold and produces the desired effect, in the secondcase, the vapor is formed outside of the oven and is injected thereintoand is absorbed by the mold and the result in both cases is the same;and a mold produced in this manner is superior to molds produced andclaimed in said patent.

By applying the oleaginous substance to the mold in the form of a vaporit is uniformly and evenly distributed over the entire surface andthroughout the structure of the mold or other article which is not thecase when the oleaginous substance is applied to the mold or otherarticle as a covering or in the manner of paint, and a mold or otherarticle treated according to this invention is much less likely to crackor warp during the process of heating or drying.

The invention is not limited to any means or apparatus for, or method ofproducing the oleaginous vapor, all that is necessary being that thesaid vapor be produced in the oven, or introduced thereinto, while themold is being heated or dried therein.

Having fully described our invention What we claim as new, and desire tosecure by Letters Patent is 1. The method of making a mold or otherarticle herein described, which consists in forming said mold or otherarticle from a composition of matter containing plaster of paris, andheating and drying said mold or other article in an oven, in thepresence of an oleaginous vapor.

2. The method of making a mold or other article herein described, Whichconsists in forming the said mold or other article from a composition ofmatter containing plaster of paris, and drying said mold or otherarticle in an oven containing an oleaginous vapor.

3. The method of making a mold or other article herein described, whichconsists in forming the said mold or other article from a composition ofmatter containing plaster of paris, and heating and drying said mold orother article in an oven containing an oleaginous vapor.

4. The method of making a mold or other article herein described, Whichconsists in forming the said mold or other article from a composition ofmatter, and drying said mold or other article in an oven in the presence of an oleaginous vapor.

In testimony that We claim the foregoing as our invention We have signedour names in presence of the subscribing Witnesses this 18th day ofSeptember 1909.

ERNST L. BOHL. ROBERT Y. BARROWS. Witnesses:

H. R. CANFIELD, C. E. MULREANY.

